Therapeutic effects of matrine on primary and metastatic breast cancer

Matrine, one of the main components extracted from a traditional Chinese herb, Sophora flavescens Ait, has displayed anti-cancer activity in several types of cancer cells. This study aims to evaluate the therapeutic benefits of matrine on primary and metastatic breast cancer. Matrine inhibited the viability of and induced apoptosis in human MCF-7 and mouse 4T1 breast cancer cells in a dose-dependent manner in vitro as shown by MTT assay, flow cytometry and laser scanning confocal microscopy. Administration of matrine inhibited the growth of primary tumors and their metastases to lungs and livers, in a dose-dependent manner, in a highly metastatic model of 4T1 breast cancer established in syngeneic Balb/c mice. Tumors from matrine-treated mice had a smaller proliferation index, shown by immunostaining with an anti-Ki-67 antibody, a greater apoptosis index, shown by TUNEL-staining, and a less microvessel density, shown by immunostaining with an anti-CD31 A antibody, compared to the controls. Western blot analysis of tumoral homogenates indicated that matrine therapy reduced the ratio of Bcl-2/Bax, downregulated the expressions of VEGF and VEGFR-2, and increased the activation of caspase-3 and caspase-9. This study suggests matrine may be a potent agent, from a natural resource, for treating metastatic breast cancer because of its anti-apoptotic, anti-proliferative and anti-angiogenic activities.

Biliary intervention augments chemotactic reaction and aggravates cholestatic liver injury in rats

Background
Intervention of the biliary system is frequently done in patients with obstructive jaundice and is associated with significant morbidity and mortality. The pathogenesis is unknown.
Materials and methods
A rat model of bile duct ligation (BDL) for 2 weeks was established in which biliary intervention was feasible by injection of normal saline through an indwelling catheter in the bile ducts. Plasma levels of C-C chemokine MCP-1 and C-X-C chemokine MIP-2 were measured by using ELISA. Blood monocytes, Kupffer cells, and neutrophils in the liver were characterized with antibodies to ED1, ED2, and myeloperoxidase (MPO). Lipid peroxidation was measured by malondialdehyde contents and apoptosis by TUNEL stain of the liver.
Results
Biliary intervention resulted in an increase of plasma MCP-1 and MIP-2 proteins by 1 h, which declined to normal level by 3 h in both sham and BDL rats. The levels in BDL rats were significantly higher than in sham at most points. There was a transient increase of ED1- and ED2-positive cells and MPO-staining cells in sham rat liver by 1 h after intervention. ED2-positive cells increased significantly by 1 h, while ED1- and MPO-positive cells decreased, yet insignificantly after intervention in BDL rats. The cell counts in BDL were constantly higher than in sham. Malondialdehyde increased precipitously in BDL by 3 h and was significantly higher than in sham throughout the study period. Parenchymal liver injury, manifested by elevated ALT, as well as apoptosis and necrosis of liver cells, was significantly increased in BDL rats, but not in sham rats.
Conclusion
Biliary intervention augments chemokine expression, precipitates lipid peroxidation, and aggravates liver injury in cholestatic rats.

Silver sulfide as a staining agent for scanning electron microscopy of nylon 6/MXD6 blends

BACKGROUND: In transmission and scanning electron microscopy imaging, the ability to obtain sufficient contrast between the components of a blend when they are both of a similar chemical structure still remains problematic. This paper investigates the domain morphology of a polymer blend containing two polyamides, nylon 6 and the semi-aromatic polyamide poly(m-xylene adipamide) (MXD6), using scanning electron microscopy in backscattered electron imaging mode. The efficiency of three staining agents, ruthenium tetroxide, phosphotungstic acid and silver sulfide, in obtaining optimum phase contrast between the two polymers is discussed.
RESULTS: The use of silver sulfide as a staining agent was found to be a fast and reliable approach which required basic sample preparation and provided excellent compositional contrast between the phases present in the nylon 6/MXD6 blends compared to the other staining agents.
CONCLUSIONS: The technique described in this paper is believed to be a novel and versatile method that has the potential to further improve the ability to study complex polymer blends where one polymer contains an aromatic ring.

Corneal staining and cell shedding during the development of solution-induced corneal staining

Purpose. This non-dispensing cross-over study was conducted to determine if lenses presoaked in Opti-Free RepleniSH (OFR) or ReNu MultiPlus (RMP) cause solution-induced corneal staining (SICS) and subsequent cell sloughing before the typical 2 h in vivo examination point.

Methods. Study lenses (PureVision) were worn bilaterally by 13 participants for periods of 15, 30, 60, and 120 min using two different contralateral care regimen pairings. The lens worn on the test eye was soaked overnight in either OFR or RMP and the control eye in Clear Care (CC). After lens removal, corneal staining was rated on a scale of 0 (negligible) to 100 (severe) for four peripheral quadrants and the central region, and the differential global staining score was calculated by subtracting baseline staining scores. Following the staining assessment, corneal cells were collected from the ocular surface using a non-contact irrigation system to determine ocular cell shedding rates.

Results. Differential global staining score with OFR was greater than CC with the differences being statistically significant at 30 and 60 min (p < 0.01). Maximum staining with RMP was significantly greater than OFR and peaked after 60 and 120 min of lens wear (p < 0.01). On average, 710 ± 470 ocular cells were collected after lens wear, with similar shedding seen independent of solution or lens wear duration (p > 0.05).

Conclusions. SICS occurred earlier but to a significantly lower degree when PureVision lenses were presoaked in OFR compared with RMP, while lenses presoaked in CC did not cause SICS. Ocular surface cell shedding after lens removal was not impacted by lens wear durations of <=2 h.

Corneal staining as a response to contact lens wear

Objective: To review the effects of contact lenses on the corneal surface.

Methods: A review of the literature and in-house research of corneal staining and its various forms of presentation.

Results: Corneal staining manifests in many different forms. The severity of staining or insult of the cornea is usually determined by the extent (area of coverage), density, and depth. The cause of staining is multifactorial, and its location is often linked to the type of lens that is being worn, the solution used to clean/disinfect the lens, the state of hydration of the soft lens, and the state of the cornea that has been affected by the lens.

Conclusions: Sodium fluorescein dye effectively highlights corneal integrity changes referred to as corneal staining. This review describes the manifestations, the cause, the mechanisms, and the methods of remediation of corneal staining.

Impact of a rub and rinse on solution-induced corneal staining

Purpose. To investigate whether the inclusion of a rub and rinse step before contact lens disinfection has an impact on solution-induced corneal staining.

Methods. This was a prospective, double-masked, single investigator study. Twenty participants were recruited for two visits, where balafilcon-A lenses were worn bilaterally for 2 h. Each pair of lenses was prepared using two different methodologies. The “control” lens was transferred from the blister pack directly into a storage case containing polyhexamethylene biguanide-based lens care solution. The contralateral “test” lens was rubbed and simultaneously rinsed using the same polyhexamethylene biguanide-based care solution, for either 60 s (visit 1) or 20 s (visit 2). Both lenses were then soaked in the solution overnight. After baseline corneal staining assessments, the lenses were inserted following a randomized contralateral model. After 2 h, lenses were removed, corneal staining was regraded, and comfort scores were obtained.

Results. Rubbed and rinsed test lenses induced significantly less corneal staining than control lenses for all participants during visit 1 (mean ± SD: 516 ± 843 vs. 2170 ± 902; p < 0.001) and visit 2 (522 ± 417 vs. 2091 ± 965; p < 0.001). There was no significant difference between the test lenses during visits 1 and 2 (p = 0.72) or controls (p = 0.50). Comfort scores did not differ between eyes (p > 0.05).

Conclusions. Corneal staining induced after 2 h of lens wear with the combination of balafilcon-A and polyhexamethylene biguanide-based lens care solution can be significantly reduced by including a rub and rinse step before overnight soaking. Further work is required to establish the longevity of this effect during the monthly wearing cycle.